fer these data easily and economically from one computer to another, despite the availability of the communications technologies to support such data exchange. The chief obstacle to achieving this capability has been the haphazard adoption of data standards for organizing, representing, and encoding clinical information so that the data can be understood and accepted by the receiving systems (Hammond, 2002). At the level of the health care organization, the lack of common data standards has prevented information sharing between commercial clinical laboratories and health care facilities, between pharmacies and health care providers regarding prescriptions, and between health care organizations and payers for reimbursement (Hammond, 2002). The lack of standards has also prevented the reuse of clinical data to meet the broad range of patient safety and quality reporting requirements, shown in Table 4-1. The first column of this table lists the data sources often associated with an electronic health record (EHR); the second, those associated with clinical information systems, decision support tools, and external data sources; the third, state, regulatory, and private-sector patient safety reporting systems; and the fourth, federal reporting systems. The fact that there is no standard means of representing the data for any of these datasets or requirements is astonishing and highlights the amount of unnecessary work performed by health care and regulatory organizations to prepare, transmit, and use what amount to custom reports. The federal government has recognized this problem and is moving forward with the integration of its safety-related systems. This study goes further by recommending common standards for the clinical and patient safety data that span the full range of data sources listed in Table 4-1. Many of the data standards required are already available; others need further development.

In the context of health care, the term data standards encompasses methods, protocols, terminologies, and specifications for the collection, exchange, storage, and retrieval of information associated with health care applications, including medical records, medications, radiological images, payment and reimbursement, medical devices and monitoring systems, and administrative processes (Washington Publishing Company, 1998). Standardizing health care data involves the following:

• Definition of data elements—determination of the data content to be collected and exchanged.

• Data interchange formats—standard formats for electronically encod-